Air inlet filter for a parenteral solution container



y 1965 R. w. BARTON ETAL 3,193,993

AIR INLET FILTER FOR A PARENTERAL SOLUTION CONTAINER Original Filed Oct.14. 1960 2 Sheets-Sheet 1 iii-TWIN y 3, 1965 R. w. BARTON ETAL 3,193,993

AIR INLET FILTER FOR A PARENTERKL SOLUTION CONTAINER Original Filed Oct.14, 1960 2 She' ets-Sheet 2.

United States Patent Office 3,193,993 Patented July 13, 1965 3,193,993Am DILET FILTER FOR A PARENTERAL SGLUTION CONTAINER Raymond W. Barton,Evansville, Ind, Hermann Heclrel,

Oxford, Ohio, and Paul Prickett and Edward G. Swenson, Evansville, ind,assignors, by mesne assignments, to Don Baxter, line, Glendale, Califi,a corporation of Nevada Griginal application Oct. 14, 1960, Ser. No.62,585, now Patent No. 3,161,310, dated Dec. 15, 1964. Divided and thisapplication Feb. 1, 1963, Ser. No. 261,926

3 Mains. (Cl. 55-385) This application is a division of the inventorscopending application Serial No. 62,585, filed October 14, 1960, now US.Patent 3,161,310 issued December 15, 1964.

This invention is concerned with an air inlet device for use with aparenteral solution container.

Parenteral solutions, designed for infusion or intravenous feeding ofpatients have commonly been packaged in glass bottles of varying sizes.Glass bottles are quite heavy, relatively expensive, subject to breakagewhen mishandled and provide a disposal problem for the hospital, as theyare not consumed by incineration.

Eflorts have been made to provide plastic solution containers ofsynthetic plastic materials. Most of the work in this field has beenconcentrated on collapsible bags of plastic film materials, but thistype of container presents several serious problems. A plastic bag isnot self-supporting and if, as frequently happens, the administration ofa solution must be interrupted to switch to blood, the administrationapparatus is disconnected from the solution container and the remainingsolution runs out. The lack of sufficient rigidity to be self-supportingmakes filling extremely difficult; and in practice the containers areformed and filled simultaneously. Automatic machines for performingthese operations are relatively slow as compared with bottle-fillingmachines, adding to the manufacturing costs. In addition, suchcontainers must be heat sealed with liquid in them. It is difiicult tomake seals of this character with consistent quality in a productionoperation.

Another problem with plastic film containers is that water vapor escapesthrough the container walls. It the containers are stored for a periodof time even as short as six to nine months, the concentration of thecontents may be seriously increased.

A principal object of this invention is the provision of a moldedplastic bottle having adequate strength and suflicient clarity to permitvisual inspection of the contents and having a temperaturecharacteristic allowing the use of heat sterilization, as in anautoclave.

One feature of the invention is the provision of a containerparticularly designed for parenteral solutions, including a bottle ofblow-molded, intermediate density polyethylene plastic material; andpreferably the bottle, which is partially deformcble but not completelycollapsible, has a first portion provided with a rupturable diaphragmfor connection with an administration set and another portion providedwith a resealable diaphragm for insertion of an air inlet device.Another feature of the invention is that the solution bottle issubstantially completely filled with parenteral solution and has aminimum air space therein. As will appear, the substantially completefill reduces the possibility of distortion of the container duringsterilization.

A further feature is that the container has a panel of transparent tapeadhesively secured to a wall thereof to improve the transmission oflight therethrough, permitting visual inspection of the contents.

Still another feature of the invention is that the bottle has a recessedbottom portion with a centrally located depending tab, having an openspace therearound between the tab and the peripheral portion of thebottle bottom. A suspension means for the bottle is attached to the taband disposable within the open space surrounding the tab when the bottlerests on the surface. A further feature is that the suspension means forthe bottle comprises a length of plastic tubing having its endstelescoped and sealed together.

Yet another feature of the invention is the provision of a bottle ofmolded plastic material having an indented area formed in the wallthereof with a pad of puncturable resealable material located in theindented area and a covering of a tape-like material overlying the padand adhered to the adjacent container wall; and more specifically, firstand second indented areas are formed adjacent each other with the end ofthe tape-like material extending partially over the second indented areato facilitate the removal of the tape.

And a further feature of the invention is the method of packaging asolution in a plastic container which comprises providing the containerwith a support, filling the container and sterilizing the supportedcontainer and contents at a temperature above the softening temperatureof the plastic material. Another feature of the packaging method is thatthe container is substantially completely filled, minimizing the airspace therein and reducing the possibility of distortion or deformationof the container during autoclaving.

A further feature of the invention is the method of ap plying a tapepanel to the wall of the container which includes the step of warmingthe container to an elevated temperature and applying the tape panel atthe elevated temperature, permitting the adhesive to fill theirregularities of the container surface. Still another feature is thestep of wetting the surface of the container with an adhesive solventbefore applying the tape, to cause the adhesive to conform intimatelywith the irregularities of the surface.

' And a further feature of the invention is the provision of an airinlet filter device for a plastic parenteral solution container in whichmeans are provided for preventing the solution wetting the filtermaterial. More specifically, the filter device includes an elongatedbody with a cannula at one end for insertion into the container and amass of filter material at the other end, remote from the cannula. In analternative structure, the air inlet device includes a manually operablevalve member between the cannula and the filter material.

Further features and advantages of the invention will be apparent fromthe following specification and from the drawings in which:

FIGURE 1 is an elevational view of a container embodying the invention;

FIGURE 2 is an elevational view of the container in use, with aninfusion set connected thereto;

FIGURE 3 is an enlarged fragmentary sectional view of the lower portionof the container, illustrating the supporting arrangement;

FIGURE 4 is an enlarged fragmentary sectional view taken generally alongthe line 44 of FIGURE 6, illustrating the air intake resealable pad andits mounting;

FIGURE 5 is an enlarged fragmentary sectional view of the neck of thecontainer and the closure therefor;

FIGURE 6 is a fragmentary elevational view of the resealable entry pad;

FIGURES 7-9 are diagrammatic views illustrating steps of the filling andsterilizing method according to the invention;

FIGURE 10 is an elevational view, partially in section, of an air inletfilter device for use with the plastic container;

FIGURE 11 is a fragmentary view, partially in section, of a modified airfilter; and

FIGURE 12 is a sectional view of another modified air filter. 7

Several basic requirements for parenteral solution containers must bemet in adapting a plastic material for such use. One of the mostimportant requirements re: lates to the ability to Withstand elevatedtemperatures,,for an extended period of time. Most parenteral solutionsprovide an excellent medium for bacterial growth, and

' ministration set ZShas a part 29 with a cannula or spike must besterilizedin the final container unless the filling Furthermore, themost practical sterilization procedure.

for parenteral products is to heat the filled containers to atemperature in excess of7220 F., and'maintain it at the elevatedtemperature for a period, as of the order of onehalf hour. 7 Such anoperation is normally carried on in an autoclave and is often referredto as autoclaving. Accordingly, it is necessary that the plasticmaterial used be such that it will not fail at this elevatedtemperature. This in itself is not too difiicult to attain with thepresently available plastics, such as the highdensity polyethylenes.However, anotherirnportant requirement is that the container be suchthat the contents can be visually inspected before use, with sufiic'ientclarity to permit observation of small particles, such as may becausedby formation of a precipitate in the solution. Hence, the material mustwhich is inserted through an outlet in-neck 21 of the container, forconducting the solution to a patient. Air is admitted to the containerZtl through a filter 32 suitably connected with the container, as willappear.

The suspension arrangement for the container .is best seen in FIGURE 3.The bottom portion 34 of container 20 is formed inwardly defining arecess surrounded by a peripheral bottom portion 35. Centrally locatedin the recess is a diagonally extending depending tab36, provided withan aperture 364: through which the suspension member 26 extends; Aplurality of feet 37 are formed on the bottom ofthe peripheral portionof the con tainer and hold the-peripheral portion'spaced from asupporting surface 38 on which the container may stand in an uprightposition. The downward extent of depending tab 36 'is such that itslower extremity is spaced above the supporting surface. The suspensionmember 26 is received within the recess surrounding tab 36 and mayextend outwardly between the peripheral bottom portion 35 of thecontainer, between the feet 37, without interfer-ringwith the stabilityof the container.

The 'suspensionfmember 26 preferably comprises a length of vinyl plastictubing having its end portions telescoped and sealed together. Theplastic .tubing supporting elementis extremely flexible and readilyassumes such permit relatively undiifused passage of light through thecontainer walls.

In addition, the container must have sufficient strength to withstandhydrostatic shocks incurred during handling and shipment and must not besubject to stress failures during aging, as the productsmay be storedfor some time before use.

A further requirement is that the plastic material shall not permitcontamination of the contents over a period of time, either directlyfrom the plastic itself, or by the slow diffusion or migration ofair-borne contaminants through thecontainer wall. r Y I foundsatisfactory when the filling and processing are cari I ried on inaccordance with the invention. H

Turning now :to the. drawings, a container 20 embodying the invention isillustrated in FIGURE 1. Container 20 is bottle-like inconfiguration,and has an opening defined by a neck 21 closed by a cap 22which is in turn covered by a plastic film seal 23. The container orhottle 20 has a generally square cross-section with rounded corners formaximum strength with greatest economy of space for packaging andstorage. In a one-liter size container, utilizing the medium densitypolyethylene material specified above, the thickness of the side panelsof the container, which are the thinnest portion of the bottle, is-

of the order of 0.015 inch. This is the'minimum thickness obtainablewith present molding techniques to achieve a tic tubing materialthroughthe opening 36a in the tab,

dipping one end in a solvent for the plastic and then telescopingtheends of the tubing; -When the solvent evaporates, the ends are firmlywelded together.

The neck .21 of containerZtl is provided with a plug or fitment 40 whichserves as a closure for the container and also provides for theconnection thereto of a suitable administration apparatus. The plug ispreferably of poly- V ethylene material, and has an outwardly extendingrim bottle with sufficient strength, particularly in the bottom portionthereof, to withstand the stresses of handling. A label 24 fixed to theside wall of the container 20 carries suitable identifying indicia fortheparenteral solution, and also provides graduated scales indicatingthe quantity of solution inthe container. 'Two reversely related :scalesare desirable, so that the quantity of solution may be determinedwhether the container is upright or inverted.

FIGURE 2 illustrates the container 20 as it is usedin 7 dispensing thesolution. The container is hung in an inverted position by a supportingelement orsuspension member 26 from a suitable carrier 27, as a hook. Anad- 41 which seats on the'surface of the. neck 21 of the container,properly positioning the plug in the neclc. After insertion, the plug isheat sealed in place, bonding the interfacebetween the inner surface ofthe neck and the outer wall surface of the plug. The plug is centrallyrecessed and is provided with an upstanding central tubular portion 42closed at its innerend by an integral, rupturable diaphragm .43. Theinner diameter of tubular portion 42"is such that it seals with thesurface of the spike or cannula 30 of the administration set uponinsertion thereofto a depth less than that sufiicient to cause thepointed end portion to rupture the diaphragm. This prevents leakageof'the contents during the attachment of theadministration set.

- Inasmuch as the container 20 is only slightly deformable orcollapsible, it is necessary to provide for the entry of air to permitthe contents :to flow out through the administration set. A side wallof'the container, adjacent the bottom thereof, is provided with a pairof indented or depressed areas 46 and 47, with the area 47 beingadjacent to and directly below the area 46. A disc of resealing rubberymaterial, as a gum rubber, is afiixed to the indented area 46'andprovides for the insertion of the spike of an air, inlet and filterdevice. The resealing disc 48 7 preferably has laminated thereto a layerof double-sided,

, securing the disc. 48 to the container wall. The sterility of the disc43 is maintained during handling and storage one side, which overliesthe disc and is sealed to the wall of the container around the disc andindented area 46. An end portion 50a of the tape strip extends partiallyover the lower indented area 47 providing a readily manually engageablesurface for grasping the tape to remove it.

The procedure followed in filling and sterilizing the container 20 isparticularly important in permitting the practitcal utilization ofpolyethylene plastic material as the container. The preferred sequenceof steps in the filling and the sterilizing operation are illustrated inFIGURES 7-9. In FIGURE 7, the plastic container 20 is shown received ina suporting sleeve or canister 54 which conforms generally with theshape of the empty container and holds it during the filling andsterilizing operation. The container 20 preferably has a sliding fitinside the supporting canister 54. Supporting canister 54 is preferablyof a reasonably rigid construction, as of sheet aluminum, and isprovided with feet 55 which support the bottom in spaced relation from asupporting surface 56 to permit circulation of steam about the canister.A slot extends across the bottom of the canister to allow steam to enterand reach container 20. The slot is so located that diagonally extendingtab 36 cannot enter it.

The empty container 20 is placed in the canister 54 and then filled, asfrom a suitable filling head 57. The parenteral solution is preferablydelivered to container 20 at an elevated temperature, as of the order of140- 190 F. This serves two functions: first, it reduces the quantity ofdissolved gases in the parenteral liquid which might be driven off andstretch the bottle during autoclaving; and second, it reduces the timerequired to bring the filled containers to sterilization temperature inthe autoclave. The container 20 is as nearly completely filled aspossible, minimizing the quantity of air trapped therein. This reducesthe danger of distortion of the container by high pressure gas when theplastic walls are softened during autoclaving. The filled container isprovided with closure plug 40 which is sealed in place.

A quantity of the filled and supported containers 20 are then placed inan autoclave 58, FIGURE 8, in which they are held on spaced shelves 59.Steam is introduced into the autoclave, as through valve 60, at atemperature of the order of 230 F. for the medium density poly ethylenematerial described above. This condition is maintained for a period ofthe order of thirty minutes to insure complete sterilization of theproduct. The temperature at which autoclaving is carried on requires apressure of the order of 8-10 pounds per square inch. The sterilizationtemperature is in the range in which the plastic material softens and isreadily deformable. The support provided by canister 54 and the absenceof an excessive volume of air in the container reduce this problem.

Following the autoclaving period, the steam within the autoclave 58 isvented, and cooling water, as at a temperature of 190 F. introduced, asthrough valve 61. An over-riding air pressure of the order of 12-16pounds per square inch is introduced into the autoclave through valve 62before or concurrently with the venting of the steam. After the bottlesare suitably cooled, they are removed from the autoclave 58, the uppersurfaces of the plug sterilized and cap 22. applied.

The label 24 which carries identifying indicia and graduationsindicating the quantity of liquid in the container, serve furtherpurposes. Molding procedures make it desirable to have a roughenedsurface on the container to facilitate removal from the mold. Thissurface irregularity diffuses light passing therethrough renderingimpossible visual observation and inspection of the contents with theaccuracy or clarity necessary. However, it has been found that if alayer of clear plastic material is adhered to the container surface, theclairity of the container is markedly increased. It is believed that thepenetration of the adhesive on the tape into the irregularities of thesurface of the blow-molded container reduces the diffraction ordispersion of light passing therethrough, and permits the requiredvisual inspection. It is preferable that adhesive-coated panels beapplied to opposite walls of the container, for maximum lighttransmission and clarity. The adhesive on the tape must be of sufficientthickness and have adequate flow characteristics to penetrate into thesurface irregularities of the plastic material. The results are improvedby applying the tape panels when the containers are warm or at elevatedtemperatures, permitting the adhesive to flow into the irregularities ofthe surface more freely; or by wetting the surface with an adhesivesolvent, as alcohol or an alcoholglycerine mixture, prior to theapplication of the panel. Transparent cellophane tape marketed byMinnesota Mining and Manufacaturing Company under the trademark Scotchhas been found satisfactory.

The indicia-bearing tape panels have the further beneficial effect ofincreasing the effective strength of the container, reducing thepossibility of rupture during handling.

The air entry patch 48 and its covering tape strip 50 are preferablyapplied to the wall of the container prior to filling. The adhesive bondbetween the patch and the bottle wall is improved by the pressureapplied thereto as a result of the weight of the container contents,while the container is confined within the sleeve 54, and at the sametime heated to a point where the adhesive is intimately bonded with boththe patch and the container wall.

For proper utilization of the resilient plastic parenteral container 20,a specially designed air inlet-filter device is desirable. When thespike of the air inlet is forced through the wall of the container, itrequires the application of a substantial pressure on the container. Theresulting deformation of the container places the contents underpressure and may force some of the contents into the air inlet devicewetting the filtering medium and ren dering it relatively unfit for use.

A novel air inlet and filter device constructionis illustrated in FIGURE10. The filter body 65 is elongated, and has a sharpened cannula orspike 66 at one end thereof, for insertion through the wall of thecontainer. The body 65 is elongated in a direction generally coaxiallywith the spike 66 and is provided at its outer end, remote from thespike, with a mass 67 of a suitable filtering material as sterilecotton. The spacing between the spike and filter material is preferablyof the order of one inch. The outer end of the elongated filter body hasa pair of air inlet holes 68 formed therein, and suitably closed priorto use as by a cap 69. If desired, a strip of adhesive-coated tape 70may be affixed to the outer end of shoulder body 65, overlying the airinlet holes 68. The tape may be lifted up to permit air to flow into theholes and replaced at will, to control the entry of air into thecontainer, and thus the administration of the parenteral solution.

A modified construction is shown in FIGURE 11 where the air inletopening 72 is formed in the end wall of the filter body 73, immediatelyadjacent the filter material 74. A removable and replacable rubber cap75 is fitted over the end of the filter body to close the open.- ing'72.

Still a further modification of the air inlet and filter device isillustrated in FIGURE 12. Here the filter body 78 has a cannula or spikeportion 79 extending from the end wall thereof and filter material 8:)is carried in the cup-like filter body. A valve member 81 is provided inthe air inlet body and seats against the end Wall from which the cannulaprojects. The valve is provided with a valve stem 82 having a portion82a which extends into the bore 79a of the spike 79 serving as a guidefor the movement of valve 81. The second portion 82b of the valve stemextends outwardly through the filter material to permit manipulation ofthe valve. With the air filter and inlet offFIGURE :1 2,.the spike isinserted through the wall of the'container'ztl with the valve 31" inclosed position. 'This prevents any of the contents of thecontainer'fr'om flowing outwardly and'wetting the filter material. Thevalve 81 may then be opened by pulling outwardly on valve stem portion32b, admitting air whenit is desiredito administer the solution.

While we have shown and described certain embodiments of our invention,it is to be understood that it is capable of many modifications.

cannula has a bore communicating with the passage of'the elongated body;

an air permeable filter sealed in and blocl ring'oif said g openpassage'of the elongated body at a'point remote from the first end;

Changes, therefore, 7 in the construction and arrangement may be madeWithout said elongated body having an airiinlet opening irra wallthereof between theair permeable filter and the second closedend,;whereby air entering said air inlet opening passes through said airpermeable filter,

i a tubular body with a passage extending between first V and secondends thereof;

a cannula extending from and connected to the first end of the tubularbody, which cannula has a bore communicating with the passage, of saidtubular body;

a any air permeable filter in said body and blocking off said passage ofthe tubular body'at a point remote from the first end thereof; 7 i 1said tubular body having an air inlet opening more remote from the firstend of the tubular body and smaller than said air permeablefilter;

manually-operable valve means in said body operable to close oii airflow from said air permeable filter to i the bore of said cannulaj andhandle means to manually selectively open and close said valve means,said handle means being connected to said valve means andextendingexternallyof said tubular, body; a

said valve means having a guide member extending longitudinallytherebeyond and into the bore of said cannula and a disk-shaped memberdisposed below said filter and overlying and sealingly engaging againstsaid bore at the first'end of the tubular body adjacentthe cannula, V V

said handle means er'rtendinglongitudinally through 7 said airpermeablefilter and terminating exteriorly i of said tubular body.

'References Cited by the Examiner 3 V UNITED STATES PATENTS 1,206,354

11/16 Nelson 1 210-429 2,100,610- 11/37 Paisley an; 55 s 2,138,936 12/38Osterberg 128214 2,581,331 1/52 Ryan et a1. 128-214 2,817,372 12/57 Barret a1. Q 128--214 2,852,024 29/58 Ryan 128-214 3,048,958 8/62 Barnes5s-s05 FOREIGN PATENTS 966,701 9/57 Germ-any.

REUBEN FRIEDMAN, Primary Examiner. I HARRY B. THORNTON, Examiner.

1. AN AIR FILTER APPARATUS FOR ADMINISTERING AIR INTO A PARENTERALLIQUID CONTAINER, WHICH AIR FILTER APPARATUS COMPRISES: AN ELONGATEDBODY WITH A PASSAGE BETWEEN A FIRST PARTIALLY CLOSED END AND A SECONDCLOSED END THEREOF; A CANNULA EXTENDING FROM AND CONNECTED TO THE FIRSTPARTIALLY CLOSED END OF SAID ELONGATED BODY, WHICH CANNULA HAS A BORECOMMUNICATING WITH THE PASSAGE OF THE ELONGATED BODY; AN AIR PERMEABLEFILTER SEALED IN AND BLOCKING OFF SAID OPEN PASSAGE OF THE ELONGATEDBODY AT A POINT REMOTE FROM THE FIRST END; SAID ELONGATED BODY HAVING ANAIR INLET OPENING IN A WALL THEREOF BETWEEN THE AIR PERMEABLE FILTER ANDTHE SECOND CLOSED END, WHEREBY AIR ENTERING SAID AIR INLET OPENINGPASSES THROUGH SAID AIR PERMEABLE FILTER PRIOR TO ENTERING THE BORE OFSAID CANNULA; AND